Surgical wire is used in many medical procedures for holding together bone.
For example, surgical wire may be used to hold together two or more pieces of the same bone, e.g., in the case of a fractured or surgically separated bone. Alternatively, surgical wire may be used to hold together two or more different bones, e.g., in the case of a surgical repair or reconstruction. Furthermore, surgical wire may also be used to reinforce a bone, e.g., in the case where a bone has been weakened by age or disease or injury.
In these and other situations, a length of surgical wire is generally wrapped around the bone which is to be held together, and then the two free ends of the wire are made fast to one another, e.g., by twisting together the two free ends of the surgical wire.
By way of example, in a so-called "total hip replacement" procedure, the top end of the patient's femur is replaced by a prosthetic device. More particularly, the top end of the patient's femur is surgically removed, and then the lower end of the prosthetic device is secured in the intramedullary canal of the femur, e.g., by tapping and cementing. In many cases, the patient's femur may be weakened, either by age or disease or injury or surgical trauma. Accordingly, in many cases the surgeon may elect to reinforce the top end of the patient's femur by wrapping a length of surgical wire around the outside of the femur and then twisting the two free ends of the wire together so as to secure the wire in place with the desired tension. See, for example, FIG. 1, which shows several lengths of surgical wire 20 secured around the upper end of a femur 22 so as to reinforce the femur about a prosthetic device 24.
By way of another example, in a so-called "open heart" procedure, the patient's sternum is typically cut down its middle so as to permit the patient's rib cage to be spread apart and the patient's heart exposed. In many cases, at the conclusion of the surgery, the surgeon may elect to wire the sternum back together using surgical wire. In particular, the sternum is wired back together by passing a length of surgical wire across the separated sternum and then twisting the two free ends of the wire together so as to secure the wire in place with the desired tension. See, for example, FIG. 2, which shows several lengths of surgical wire 20 holding together a sternum 26.
By way of still another example, and referring now to FIG. 3, surgical wires 20 may also be used to hold a bone graft 28 in place in a spinal column 30.
Conventional surgical wires are generally of two types: (1) a single elongated solid strand of metal, such as stainless steel; and (2) a cable including a multiplicity of elongated thin strands of metal. The former construction is generally of greater tensile strength than the latter construction, and is generally less likely to give way or break down over extended periods of time. However, a surgical wire formed out of a single strand of metal is typically fairly stiff and hence difficult to guide around bone. On the other hand, while the cable construction generally provides the flexibility desired by physicians for guiding around bone, it is generally lacking in strength and more likely to fail in due course.
It is, therefore, desirable to have available surgical wire having the flexibility of the cable type and the strength of the solid strand type.